Ventilating arrangement in dish washing machines

ABSTRACT

In a dish washing machine having a housing with a dish washing chamber open at one side and a shutter pivotally connected to said housing by a horizontal axis for closing or opening said housing open side, a ventilating arrangement is provided through said shutter in which a valveis normally retained in a position closing a passage through said shutter by an electromagnet controlled pawl and a weight connected to said valve opens the same when said pawl is released and again causes said valve to engage said pawl when said shutter is pivoted to its housing opening position.

United-1 States Patent Johansson et a].

VENTILATING ARRANGEMENT IN DISH WASHING MACHINES Inventors: Rolf Johansson, Lindgatan 19,

53400 Varia; Erik Hojer, Solhagsvagen 45c, 53100 Lidkoping, both of Sweden Filed: Oct. 3, 1970 Appl. No.: 86,874

Foreign Application Priority Data Nov. 18,1969 Sweden ..l5/796/169 US. Cl. ..312/313, 16/81, 62/410, 134/58 DL, 232/35, 312/236, 312/292 Int. Cl. ..A47b 96/00 Field of Search....134/56 D, 57 D, 57 DL, 58 D, 134/58 DL; 16/81, 152; 232/35; 312/292; 62/410; 312/213, 236

References Cited UNITED STATES PATENTS V 476,321 6/1892 Smith ..232/35 736,522 8/1903 Hopkins ..312/292 772,128 10/1904 Burnham ..232/35 X 3,049,391 8/1962 Meeker et a1. ..312/292 X 3,092,122 6/1963 Guth ..134/58 D 3,210,144 10/1965 Ullman, Jr., et a1. ..312/229 3,233,782 2/1966 Ullman, Jr., et a1.....134/58 D X 3,398,756 8/1968 Kauffman ..134/58 D Primary Examiner-Robert L. Bleutge Attorney-Linton & Linton [5 7] ABSTRACT In a dish washing machine having a housing with a dish washing chamber open at one side and a shutter pivotally connected to said housing by a horizontal axis for closing or opening said housing open side, a ventilating arrangement is provided through said shutter in which a valveis normally retained in a position closing a passage through said shutter by an electromagnet controlled pawl and a weight connected to said valve opens the same when said pawl is released and again causes said valve to engage said pawl when said shutter is pivoted to its housing opening position.

3 Claims, 3 Drawing Figures PATENTEDAUB 1 I972 mmvrons R LF TOHHNSSO/Ynno ERIK HOJU? BY M r PATENTED E I972 3.680.940

SHEET 2 [IF 2 INVENTORS ROLF TOHQNSSONmw ERIK HOJER ATT RNEYS VENTILATING ARRANGEMENT IN DISH WASHING MACHINES The present invention relates to ventilating arrangements in dish washing machines, which have a dish washing chamber arranged in a housing, and wherein it is possible to close said chamber by means of a shutter,

which for its opening and closing operations is pivotably mounted around a substantially horizontal axis; and a program control device for carrying out the operations of the dish washing cycle, said ventilating arrangement being equipped with a duct arranged in the shutter, said duct having an inner opening communicating to the dish washing chamber, and an outer opening communicating with the surrounding air, and a valve, arranged in the passage of the duct, in one position'arranged to keep the passage closed and in another position to keep the passage open.

In dish washing machines with a closed dish washing chamber, in which the dishes from time to time are put to be washed once the machine is filled, and subsequently after the washing operation are dried,

preferably by heating of the air in the dish washing chamber, some kind of ventilation during the drying cycle of the operation is suitably arranged in said chamber. On the other hand the dish washing chamber shall be closed during the period before the dish washing operation, in order not to render said operation difficult by the dishes getting dry, and also during the dish washing operation in order to reduce the noise from the machine and to impede unnecessary escape of water steam. The ventilation can be arranged by means of a lower ventilating opening, which is always open, and an upper opening, which can be closed by means of a scuttle, valve or similar. Arrangements to automatically keep the valve open during the drying cycle while keeping it closed during the dish washing cycle are known. Such arrangements according to the prior art are conwashing period, to be maintained open during the drynected with a programming device for carrying out the dish washing and drying cycle, which device opens the valve when the dish washing operation is terminated and closes the valve when a new dish washing operation is started. In another arrangement according to the prior art the programming device causes the charging shutter of the machine to be opened when the drying cycle begins, no particular ventilating valve thus existing, and said shutter can thereafter be manually closed, when the cleaned dishes have been removed and new dishes to be washed are placed in the machine.

As to the above arrangements according to the prior art the first one mentioned has the drawback that the v ventilating valve will be in open position not only during the drying cycle but also during said period of storing, which as hinted brings with it the risk of the foodleavings adhering to the dishes to be washed getting dry, while the other arrangement has the drawback that the large charging shutter of the machine will be open during the whole drying cycle and remain so until it is manually closed, which brings with it the risk of letting in dust and moreover is inconvenient from the point of view of space, especially when the machine is installed in narrow thoroughways.

It is an object of the present invention to eliminate these drawbacks by providing a ventilating arrangement in which the ventilation takes place through an opening provided with a valve, said valve being arranged to automatically open up at the end of the dish ing cycle and to be automatically closed as soon as the charging shutter of the machine is opened after the last mentioned cycle. The valve is thus, under practical conditions, closed after that the clean dishes, which have been washed, have been removed and the machine again has been prepared for the putting in of new loads of dishes to be washed.

Said object of the invention is obtained by making the ventilating arrangement in such a manner that it is characterized by a weight being connected with the valve in such a manner that the force of gravity tends to open the valve when the shutter is closed, whilewhen the shutter is open it tends to close the valve by means of displacement relative to the vertical line during the pivoting movement of the shutter; and by a locking member being arranged to keep the valve in closed position, but also permitting the valve to be released for opening by means of the weight upon an impulse from the programming device.

A suitable embodiment of the invention will now be described with reference to the accompanying drawings, in which FIG. 1 illustrates the ventilating arrangement in a partly sectional side elevational view with the valve in closed position,

FIG. 2 is a corresponding view of the ventilating arrangement with the valve in opened up condition, and

FIG. 3 finally is a front view of the ventilating arrangement as seen from the right in FIGS. 1 and 2.

The dish washing machine is supposed to be of conventional type for household purpose having a dish washing chamber arranged in a housing and it is possible to open said chamber by means of a shutter which can be pivoted outwards and downwards around a horizontal axis. The dish washing machine is shown with double dotted and dashed lines in FIGS. 1 and 3, the washing, in FIG. 1, being indicated by l, the upper wall of the housing by 2 and the shutter by 3. The shutter 3 is pivotable in FIG. 1 downwards to the right around an axis arranged at the lower edge (not shown) of the shutter with said axis extending at a right angle to the plane of the sheet (FIG. 1). The shutter 3 is provided with a sealing edge 4 cooperating with the housing 2, said edge having a sealing gasket (not shown) of resilient material, a handle 5 and a panel 6, on which the operating means of the machine are mounted. The ventilating arrangement is designed as a unit, which can be screwed onto the shutter and comprises a duct 7 having an outer opening 8 and an inner opening 9. The outer opening 8 is via a protective grill penetrating the panel 6 communicating with the surrounding air, and the inner opening 9 is communicating with the dish washing chamber 1 and is provided with a splash guard 13 with an inwards flanged edge 27, which guard is fastened by means of screws 11 to warts 12. In the passage 14 of the duct 7 between its openings 8, 9, a scuttle valve 16 is pivotally arranged around a shaft 15. The valve 16 can be pivoted between two positions, in one of which, while, it, together with a short wall 17, is closing the passage 14, while in the other position, the passage is open, so that the openings 8, 9 are in communication with each other. One end of the shaft 15 of the valve protruding outside of the duct 7 is bent thereby forming an arm 18. On this arm 18 a weight 19 is placed, which when the valve is closed, FIG. 1, occupies an inclined position to the vertical line as is shown in FIG. 1, thereby tending to open the valve 16. In order to maintain the valve in its closed position a pawl 21 pivotable around a shaft is provided, which pawl cooperates with a plate 22 mounted for example by brazing on the shaft 15 of the valve. The pawl 21 tends by its weight to occupy a blocking position, but is arranged so that it can be lifted up from said position by means of an electromagnet 23, through the pull rod 24 attached to a wire 25 connected with the pawl 21. A number a screw warts. 26 are arranged for the purpose of fastening the ventilating arrangement in the shutter 3.

The functioning of the ventilating arrangement of the embodiment described is as follows:

During the dish. washing operation the parts of the ventilating arrangement shall occupy the position illustrated in FIG. 1, in which the shutter 3 and the valve 16 are closed, so that steam cannot escape from the dish washing chamber 1. The valve is firmly maintained in its closed position by cooperation between the pawl 21 and the plate 22. The programming device is arranged to the effect that when the washing operation is terminated a current pulse is sent to the pulling electromagnet 23, so that via the wire 25, the pull rod 24 will lift the pawl 21, thereby releasing the shaft 15 of the valve, whereupon the weight 19 pivots the valve 16 to the open position illustrated in FIG. 2. The valve is now kept open until the shutter 3 is opened, during which operation said shutter as mentioned above is tilted down from a vertical to a horizontal or almost horizontal position. Thereby the torque action of the weight 19 on the axis 15 of the valve will be reversed, so that it tends to close the valve 16, which effect also is obtained.

When the valve 16 has been closed the pawl 21 again is activated, so that the valve will remain in its closed position also after the shutter 3 again has been closed. The valve can now only be opened by a new current pulse energizing the electromagnet 23, which takes place when the next drying cycle is commenced.

By the arrangement described, an impulse from the programming device of the machine causes the opening of the valve at the beginning of the drying cycle and the closing of the valve is caused as soon as the adjustment shutter has been opened after the drying period is obtained, said operation usually meaning that the clean washed dishes are taken out and new soiled dishes are put in from time to time, it therefore being desirable that the valve is closed. However, it may happen that during the very drying period the shutter is opened in order to remove some separate piece of the dishes under treatment, which would mean that the valve would be closed and remain closed for the rest of the drying cycle, which is not desirable. It is therefore practical to have the programming device arranged to the effect that it can deliver a number of repeated current pulses to the pulling electromagnet during the drying period. Generally it is not convenient to let the magnet be continuously energized during the whole of the drying cycle, as under such circumstances it may get too hot.

The embodiment described is only chosen by way of seats a fsfiasigassavaatist Qatari; from the basic idea of the invention.

What we claim is:

l. A ventilating arrangement for dish washing machines, comprising a housing having a dish washing chamber, a shutter for opening and closing said chamber being pivotally mounted around a substantially horizontal axis, said ventilating arrangement having a duct arranged in said shutter, said duct having an inner opening communicating with said dish washing chamber and an outer opening communicating with the outside atmosphere, and a valve pivotally mounted in said duct, and capablein one position to keep said duct closed and in another position to keep said duct open, a weight being connected to said valve in such a manner that the force of gravity of said weight tends to open said valve when said shutter is closed, while, when said shutter is open, it tends to close the valve by means of displacement of said weight relative to a vertical line during the pivoting movement of said shutter and an electromagnet operated locking member being arranged to keep said valve in its closed position, but also permitting said valve to be released for opening by means of said weight upon operation of said electromagnet.

2. A ventilating arrangement according to claim 1, including a shaft in said duct pivotally supporting said valve, and an arm mounted on said shaft attached to said weight.

3. A ventilating arrangement according to claim 2 including a locking member pivotally mounted in said duct and operable by said electromagnet for being moved into a position releasing said valve upon said electromagnet being energized. 

1. A ventilating arrangement for dish washing machines, comprising a housing having a dish washing chamber, a shutter for opening and closing said chamber being pivotally mounted around a substantially horizontal axis, said ventilating arrangement having a duct arranged in said shutter, said duct having an inner opening communicating with said dish washing chamber and an outer opening communicaTing with the outside atmosphere, and a valve pivotally mounted in said duct, and capable in one position to keep said duct closed and in another position to keep said duct open, a weight being connected to said valve in such a manner that the force of gravity of said weight tends to open said valve when said shutter is closed, while, when said shutter is open, it tends to close the valve by means of displacement of said weight relative to a vertical line during the pivoting movement of said shutter and an electromagnet operated locking member being arranged to keep said valve in its closed position, but also permitting said valve to be released for opening by means of said weight upon operation of said electromagnet.
 2. A ventilating arrangement according to claim 1, including a shaft in said duct pivotally supporting said valve, and an arm mounted on said shaft attached to said weight.
 3. A ventilating arrangement according to claim 2 including a locking member pivotally mounted in said duct and operable by said electromagnet for being moved into a position releasing said valve upon said electromagnet being energized. 